#include <libavutil/imgutils.h>
#include <libavutil/mem.h>
#include <libavutil/pixfmt.h>
+#include <libavutil/opt.h>
#include <libswscale/swscale.h>
}
#include "ffmpeg_util.h"
#include "flags.h"
#include "image_input.h"
+#include "ref_counted_frame.h"
+#include "timebase.h"
#define FRAME_SIZE (8 << 20) // 8 MB.
using namespace std;
using namespace std::chrono;
using namespace bmusb;
+using namespace movit;
namespace {
return (buf.st_mtim.tv_sec != ts.tv_sec || buf.st_mtim.tv_nsec != ts.tv_nsec);
}
+bool is_full_range(const AVPixFmtDescriptor *desc)
+{
+ // This is horrible, but there's no better way that I know of.
+ return (strchr(desc->name, 'j') != nullptr);
+}
+
+AVPixelFormat decide_dst_format(AVPixelFormat src_format, bmusb::PixelFormat dst_format_type)
+{
+ if (dst_format_type == bmusb::PixelFormat_8BitBGRA) {
+ return AV_PIX_FMT_BGRA;
+ }
+ if (dst_format_type == FFmpegCapture::PixelFormat_NV12) {
+ return AV_PIX_FMT_NV12;
+ }
+
+ assert(dst_format_type == bmusb::PixelFormat_8BitYCbCrPlanar);
+
+ // If this is a non-Y'CbCr format, just convert to 4:4:4 Y'CbCr
+ // and be done with it. It's too strange to spend a lot of time on.
+ // (Let's hope there's no alpha.)
+ const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_format);
+ if (src_desc == nullptr ||
+ src_desc->nb_components != 3 ||
+ (src_desc->flags & AV_PIX_FMT_FLAG_RGB)) {
+ return AV_PIX_FMT_YUV444P;
+ }
+
+ // The best for us would be Cb and Cr together if possible,
+ // but FFmpeg doesn't support that except in the special case of
+ // NV12, so we need to go to planar even for the case of NV12.
+ // Thus, look for the closest (but no worse) 8-bit planar Y'CbCr format
+ // that matches in color range. (This will also include the case of
+ // the source format already being acceptable.)
+ bool src_full_range = is_full_range(src_desc);
+ const char *best_format = "yuv444p";
+ unsigned best_score = numeric_limits<unsigned>::max();
+ for (const AVPixFmtDescriptor *desc = av_pix_fmt_desc_next(nullptr);
+ desc;
+ desc = av_pix_fmt_desc_next(desc)) {
+ // Find planar Y'CbCr formats only.
+ if (desc->nb_components != 3) continue;
+ if (desc->flags & AV_PIX_FMT_FLAG_RGB) continue;
+ if (!(desc->flags & AV_PIX_FMT_FLAG_PLANAR)) continue;
+ if (desc->comp[0].plane != 0 ||
+ desc->comp[1].plane != 1 ||
+ desc->comp[2].plane != 2) continue;
+
+ // 8-bit formats only.
+ if (desc->flags & AV_PIX_FMT_FLAG_BE) continue;
+ if (desc->comp[0].depth != 8) continue;
+
+ // Same or better chroma resolution only.
+ int chroma_w_diff = desc->log2_chroma_w - src_desc->log2_chroma_w;
+ int chroma_h_diff = desc->log2_chroma_h - src_desc->log2_chroma_h;
+ if (chroma_w_diff < 0 || chroma_h_diff < 0)
+ continue;
+
+ // Matching full/limited range only.
+ if (is_full_range(desc) != src_full_range)
+ continue;
+
+ // Pick something with as little excess chroma resolution as possible.
+ unsigned score = (1 << (chroma_w_diff)) << chroma_h_diff;
+ if (score < best_score) {
+ best_score = score;
+ best_format = desc->name;
+ }
+ }
+ return av_get_pix_fmt(best_format);
+}
+
+YCbCrFormat decode_ycbcr_format(const AVPixFmtDescriptor *desc, const AVFrame *frame)
+{
+ YCbCrFormat format;
+ AVColorSpace colorspace = av_frame_get_colorspace(frame);
+ switch (colorspace) {
+ case AVCOL_SPC_BT709:
+ format.luma_coefficients = YCBCR_REC_709;
+ break;
+ case AVCOL_SPC_BT470BG:
+ case AVCOL_SPC_SMPTE170M:
+ case AVCOL_SPC_SMPTE240M:
+ format.luma_coefficients = YCBCR_REC_601;
+ break;
+ case AVCOL_SPC_BT2020_NCL:
+ format.luma_coefficients = YCBCR_REC_2020;
+ break;
+ case AVCOL_SPC_UNSPECIFIED:
+ format.luma_coefficients = (frame->height >= 720 ? YCBCR_REC_709 : YCBCR_REC_601);
+ break;
+ default:
+ fprintf(stderr, "Unknown Y'CbCr coefficient enum %d from FFmpeg; choosing Rec. 709.\n",
+ colorspace);
+ format.luma_coefficients = YCBCR_REC_709;
+ break;
+ }
+
+ format.full_range = is_full_range(desc);
+ format.num_levels = 1 << desc->comp[0].depth;
+ format.chroma_subsampling_x = 1 << desc->log2_chroma_w;
+ format.chroma_subsampling_y = 1 << desc->log2_chroma_h;
+
+ switch (frame->chroma_location) {
+ case AVCHROMA_LOC_LEFT:
+ format.cb_x_position = 0.0;
+ format.cb_y_position = 0.5;
+ break;
+ case AVCHROMA_LOC_CENTER:
+ format.cb_x_position = 0.5;
+ format.cb_y_position = 0.5;
+ break;
+ case AVCHROMA_LOC_TOPLEFT:
+ format.cb_x_position = 0.0;
+ format.cb_y_position = 0.0;
+ break;
+ case AVCHROMA_LOC_TOP:
+ format.cb_x_position = 0.5;
+ format.cb_y_position = 0.0;
+ break;
+ case AVCHROMA_LOC_BOTTOMLEFT:
+ format.cb_x_position = 0.0;
+ format.cb_y_position = 1.0;
+ break;
+ case AVCHROMA_LOC_BOTTOM:
+ format.cb_x_position = 0.5;
+ format.cb_y_position = 1.0;
+ break;
+ default:
+ fprintf(stderr, "Unknown chroma location coefficient enum %d from FFmpeg; choosing Rec. 709.\n",
+ frame->chroma_location);
+ format.cb_x_position = 0.5;
+ format.cb_y_position = 0.5;
+ break;
+ }
+
+ format.cr_x_position = format.cb_x_position;
+ format.cr_y_position = format.cb_y_position;
+ return format;
+}
+
} // namespace
FFmpegCapture::FFmpegCapture(const string &filename, unsigned width, unsigned height)
- : filename(filename), width(width), height(height)
+ : filename(filename), width(width), height(height), video_timebase{1, 1}
{
// Not really used for anything.
description = "Video: " + filename;
+
+ avformat_network_init(); // In case someone wants this.
}
FFmpegCapture::~FFmpegCapture()
if (has_dequeue_callbacks) {
dequeue_cleanup_callback();
}
+ avresample_free(&resampler);
}
void FFmpegCapture::configure_card()
set_video_frame_allocator(owned_video_frame_allocator.get());
}
if (audio_frame_allocator == nullptr) {
- owned_audio_frame_allocator.reset(new MallocFrameAllocator(65536, NUM_QUEUED_AUDIO_FRAMES));
+ // Audio can come out in pretty large chunks, so increase from the default 1 MB.
+ owned_audio_frame_allocator.reset(new MallocFrameAllocator(1 << 20, NUM_QUEUED_AUDIO_FRAMES));
set_audio_frame_allocator(owned_audio_frame_allocator.get());
}
}
string pathname = search_for_file(filename);
if (filename.empty()) {
fprintf(stderr, "%s not found, sleeping one second and trying again...\n", filename.c_str());
+ send_disconnected_frame();
producer_thread_should_quit.sleep_for(seconds(1));
continue;
}
if (!play_video(pathname)) {
// Error.
fprintf(stderr, "Error when playing %s, sleeping one second and trying again...\n", pathname.c_str());
+ send_disconnected_frame();
producer_thread_should_quit.sleep_for(seconds(1));
continue;
}
}
}
+void FFmpegCapture::send_disconnected_frame()
+{
+ // Send an empty frame to signal that we have no signal anymore.
+ FrameAllocator::Frame video_frame = video_frame_allocator->alloc_frame();
+ if (video_frame.data) {
+ VideoFormat video_format;
+ video_format.width = width;
+ video_format.height = height;
+ video_format.stride = width * 4;
+ video_format.frame_rate_nom = 60;
+ video_format.frame_rate_den = 1;
+ video_format.is_connected = false;
+
+ video_frame.len = width * height * 4;
+ memset(video_frame.data, 0, video_frame.len);
+
+ frame_callback(-1, AVRational{1, TIMEBASE}, -1, AVRational{1, TIMEBASE}, timecode++,
+ video_frame, /*video_offset=*/0, video_format,
+ FrameAllocator::Frame(), /*audio_offset=*/0, AudioFormat());
+ }
+}
+
bool FFmpegCapture::play_video(const string &pathname)
{
// Note: Call before open, not after; otherwise, there's a race.
return false;
}
- const AVCodecParameters *codecpar = format_ctx->streams[video_stream_index]->codecpar;
- AVRational video_timebase = format_ctx->streams[video_stream_index]->time_base;
- AVCodecContextWithDeleter codec_ctx = avcodec_alloc_context3_unique(nullptr);
- if (avcodec_parameters_to_context(codec_ctx.get(), codecpar) < 0) {
- fprintf(stderr, "%s: Cannot fill codec parameters\n", pathname.c_str());
+ int audio_stream_index = find_stream_index(format_ctx.get(), AVMEDIA_TYPE_AUDIO);
+
+ // Open video decoder.
+ const AVCodecParameters *video_codecpar = format_ctx->streams[video_stream_index]->codecpar;
+ AVCodec *video_codec = avcodec_find_decoder(video_codecpar->codec_id);
+ video_timebase = format_ctx->streams[video_stream_index]->time_base;
+ AVCodecContextWithDeleter video_codec_ctx = avcodec_alloc_context3_unique(nullptr);
+ if (avcodec_parameters_to_context(video_codec_ctx.get(), video_codecpar) < 0) {
+ fprintf(stderr, "%s: Cannot fill video codec parameters\n", pathname.c_str());
return false;
}
- AVCodec *codec = avcodec_find_decoder(codecpar->codec_id);
- if (codec == nullptr) {
- fprintf(stderr, "%s: Cannot find decoder\n", pathname.c_str());
+ if (video_codec == nullptr) {
+ fprintf(stderr, "%s: Cannot find video decoder\n", pathname.c_str());
return false;
}
- if (avcodec_open2(codec_ctx.get(), codec, nullptr) < 0) {
- fprintf(stderr, "%s: Cannot open decoder\n", pathname.c_str());
+ if (avcodec_open2(video_codec_ctx.get(), video_codec, nullptr) < 0) {
+ fprintf(stderr, "%s: Cannot open video decoder\n", pathname.c_str());
return false;
}
- unique_ptr<AVCodecContext, decltype(avcodec_close)*> codec_ctx_cleanup(
- codec_ctx.get(), avcodec_close);
+ unique_ptr<AVCodecContext, decltype(avcodec_close)*> video_codec_ctx_cleanup(
+ video_codec_ctx.get(), avcodec_close);
+
+ // Open audio decoder, if we have audio.
+ AVCodecContextWithDeleter audio_codec_ctx = avcodec_alloc_context3_unique(nullptr);
+ if (audio_stream_index != -1) {
+ const AVCodecParameters *audio_codecpar = format_ctx->streams[audio_stream_index]->codecpar;
+ audio_timebase = format_ctx->streams[audio_stream_index]->time_base;
+ if (avcodec_parameters_to_context(audio_codec_ctx.get(), audio_codecpar) < 0) {
+ fprintf(stderr, "%s: Cannot fill audio codec parameters\n", pathname.c_str());
+ return false;
+ }
+ AVCodec *audio_codec = avcodec_find_decoder(audio_codecpar->codec_id);
+ if (audio_codec == nullptr) {
+ fprintf(stderr, "%s: Cannot find audio decoder\n", pathname.c_str());
+ return false;
+ }
+ if (avcodec_open2(audio_codec_ctx.get(), audio_codec, nullptr) < 0) {
+ fprintf(stderr, "%s: Cannot open audio decoder\n", pathname.c_str());
+ return false;
+ }
+ }
+ unique_ptr<AVCodecContext, decltype(avcodec_close)*> audio_codec_ctx_cleanup(
+ audio_codec_ctx.get(), avcodec_close);
internal_rewind();
- double rate = 1.0;
-
- unique_ptr<SwsContext, decltype(sws_freeContext)*> sws_ctx(nullptr, sws_freeContext);
- int sws_last_width = -1, sws_last_height = -1;
// Main loop.
while (!producer_thread_should_quit.should_quit()) {
- // Process any queued commands from other threads.
- vector<QueuedCommand> commands;
- {
- lock_guard<mutex> lock(queue_mu);
- swap(commands, command_queue);
+ if (process_queued_commands(format_ctx.get(), pathname, last_modified, /*rewound=*/nullptr)) {
+ return true;
}
- for (const QueuedCommand &cmd : commands) {
- switch (cmd.command) {
- case QueuedCommand::REWIND:
- if (av_seek_frame(format_ctx.get(), /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) {
- fprintf(stderr, "%s: Rewind failed, stopping play.\n", pathname.c_str());
- }
- // If the file has changed since last time, return to get it reloaded.
- // Note that depending on how you move the file into place, you might
- // end up corrupting the one you're already playing, so this path
- // might not trigger.
- if (changed_since(pathname, last_modified)) {
- return true;
- }
- internal_rewind();
- break;
+ UniqueFrame audio_frame = audio_frame_allocator->alloc_frame();
+ AudioFormat audio_format;
- case QueuedCommand::CHANGE_RATE:
- start = next_frame_start;
- pts_origin = last_pts;
- rate = cmd.new_rate;
- break;
- }
+ int64_t audio_pts;
+ bool error;
+ AVFrameWithDeleter frame = decode_frame(format_ctx.get(), video_codec_ctx.get(), audio_codec_ctx.get(),
+ pathname, video_stream_index, audio_stream_index, audio_frame.get(), &audio_format, &audio_pts, &error);
+ if (error) {
+ return false;
}
-
- // Read packets until we have a frame or there are none left.
- int frame_finished = 0;
- AVFrameWithDeleter frame = av_frame_alloc_unique();
- bool eof = false;
- do {
- AVPacket pkt;
- unique_ptr<AVPacket, decltype(av_packet_unref)*> pkt_cleanup(
- &pkt, av_packet_unref);
- av_init_packet(&pkt);
- pkt.data = nullptr;
- pkt.size = 0;
- if (av_read_frame(format_ctx.get(), &pkt) == 0) {
- if (pkt.stream_index != video_stream_index) {
- // Ignore audio for now.
- continue;
- }
- if (avcodec_send_packet(codec_ctx.get(), &pkt) < 0) {
- fprintf(stderr, "%s: Cannot send packet to codec.\n", pathname.c_str());
- return false;
- }
- } else {
- eof = true; // Or error, but ignore that for the time being.
- }
-
- int err = avcodec_receive_frame(codec_ctx.get(), frame.get());
- if (err == 0) {
- frame_finished = true;
- break;
- } else if (err != AVERROR(EAGAIN)) {
- fprintf(stderr, "%s: Cannot receive frame from codec.\n", pathname.c_str());
- return false;
- }
- } while (!eof);
-
- if (!frame_finished) {
+ if (frame == nullptr) {
// EOF. Loop back to the start if we can.
if (av_seek_frame(format_ctx.get(), /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) {
fprintf(stderr, "%s: Rewind failed, not looping.\n", pathname.c_str());
return true;
}
+ if (video_codec_ctx != nullptr) {
+ avcodec_flush_buffers(video_codec_ctx.get());
+ }
+ if (audio_codec_ctx != nullptr) {
+ avcodec_flush_buffers(audio_codec_ctx.get());
+ }
// If the file has changed since last time, return to get it reloaded.
// Note that depending on how you move the file into place, you might
// end up corrupting the one you're already playing, so this path
continue;
}
- if (sws_ctx == nullptr || sws_last_width != frame->width || sws_last_height != frame->height) {
- sws_ctx.reset(
- sws_getContext(frame->width, frame->height, (AVPixelFormat)frame->format,
- width, height, AV_PIX_FMT_RGBA,
- SWS_BICUBIC, nullptr, nullptr, nullptr));
- sws_last_width = frame->width;
- sws_last_height = frame->height;
- }
- if (sws_ctx == nullptr) {
- fprintf(stderr, "%s: Could not create scaler context\n", pathname.c_str());
+ VideoFormat video_format = construct_video_format(frame.get(), video_timebase);
+ UniqueFrame video_frame = make_video_frame(frame.get(), pathname, &error);
+ if (error) {
return false;
}
- VideoFormat video_format;
- video_format.width = width;
- video_format.height = height;
- video_format.stride = width * 4;
- video_format.frame_rate_nom = video_timebase.den;
- video_format.frame_rate_den = av_frame_get_pkt_duration(frame.get()) * video_timebase.num;
- video_format.has_signal = true;
- video_format.is_connected = true;
-
- next_frame_start = compute_frame_start(frame->pts, pts_origin, video_timebase, start, rate);
- last_pts = frame->pts;
+ for ( ;; ) {
+ if (last_pts == 0 && pts_origin == 0) {
+ pts_origin = frame->pts;
+ }
+ next_frame_start = compute_frame_start(frame->pts, pts_origin, video_timebase, start, rate);
+ video_frame->received_timestamp = next_frame_start;
+ bool finished_wakeup = producer_thread_should_quit.sleep_until(next_frame_start);
+ if (finished_wakeup) {
+ if (audio_frame->len > 0) {
+ assert(audio_pts != -1);
+ }
+ frame_callback(frame->pts, video_timebase, audio_pts, audio_timebase, timecode++,
+ video_frame.get_and_release(), 0, video_format,
+ audio_frame.get_and_release(), 0, audio_format);
+ break;
+ } else {
+ if (producer_thread_should_quit.should_quit()) break;
- FrameAllocator::Frame video_frame = video_frame_allocator->alloc_frame();
- if (video_frame.data != nullptr) {
- uint8_t *pic_data[4] = { video_frame.data, nullptr, nullptr, nullptr };
- int linesizes[4] = { int(video_format.stride), 0, 0, 0 };
- sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes);
- video_frame.len = video_format.stride * height;
- video_frame.received_timestamp = next_frame_start;
+ bool rewound = false;
+ if (process_queued_commands(format_ctx.get(), pathname, last_modified, &rewound)) {
+ return true;
+ }
+ // If we just rewound, drop this frame on the floor and be done.
+ if (rewound) {
+ break;
+ }
+ // OK, we didn't, so probably a rate change. Recalculate next_frame_start,
+ // but if it's now in the past, we'll reset the origin, so that we don't
+ // generate a huge backlog of frames that we need to run through quickly.
+ next_frame_start = compute_frame_start(frame->pts, pts_origin, video_timebase, start, rate);
+ steady_clock::time_point now = steady_clock::now();
+ if (next_frame_start < now) {
+ pts_origin = frame->pts;
+ start = next_frame_start = now;
+ }
+ }
}
-
- FrameAllocator::Frame audio_frame;
- AudioFormat audio_format;
- audio_format.bits_per_sample = 32;
- audio_format.num_channels = 8;
-
- producer_thread_should_quit.sleep_until(next_frame_start);
- frame_callback(timecode++,
- video_frame, 0, video_format,
- audio_frame, 0, audio_format);
+ last_pts = frame->pts;
}
return true;
}
pts_origin = last_pts = 0;
start = next_frame_start = steady_clock::now();
}
+
+bool FFmpegCapture::process_queued_commands(AVFormatContext *format_ctx, const std::string &pathname, timespec last_modified, bool *rewound)
+{
+ // Process any queued commands from other threads.
+ vector<QueuedCommand> commands;
+ {
+ lock_guard<mutex> lock(queue_mu);
+ swap(commands, command_queue);
+ }
+ for (const QueuedCommand &cmd : commands) {
+ switch (cmd.command) {
+ case QueuedCommand::REWIND:
+ if (av_seek_frame(format_ctx, /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) {
+ fprintf(stderr, "%s: Rewind failed, stopping play.\n", pathname.c_str());
+ }
+ // If the file has changed since last time, return to get it reloaded.
+ // Note that depending on how you move the file into place, you might
+ // end up corrupting the one you're already playing, so this path
+ // might not trigger.
+ if (changed_since(pathname, last_modified)) {
+ return true;
+ }
+ internal_rewind();
+ if (rewound != nullptr) {
+ *rewound = true;
+ }
+ break;
+
+ case QueuedCommand::CHANGE_RATE:
+ // Change the origin to the last played frame.
+ start = compute_frame_start(last_pts, pts_origin, video_timebase, start, rate);
+ pts_origin = last_pts;
+ rate = cmd.new_rate;
+ break;
+ }
+ }
+ return false;
+}
+
+namespace {
+
+} // namespace
+
+AVFrameWithDeleter FFmpegCapture::decode_frame(AVFormatContext *format_ctx, AVCodecContext *video_codec_ctx, AVCodecContext *audio_codec_ctx,
+ const std::string &pathname, int video_stream_index, int audio_stream_index,
+ FrameAllocator::Frame *audio_frame, AudioFormat *audio_format, int64_t *audio_pts, bool *error)
+{
+ *error = false;
+
+ // Read packets until we have a frame or there are none left.
+ bool frame_finished = false;
+ AVFrameWithDeleter audio_avframe = av_frame_alloc_unique();
+ AVFrameWithDeleter video_avframe = av_frame_alloc_unique();
+ bool eof = false;
+ *audio_pts = -1;
+ do {
+ AVPacket pkt;
+ unique_ptr<AVPacket, decltype(av_packet_unref)*> pkt_cleanup(
+ &pkt, av_packet_unref);
+ av_init_packet(&pkt);
+ pkt.data = nullptr;
+ pkt.size = 0;
+ if (av_read_frame(format_ctx, &pkt) == 0) {
+ if (pkt.stream_index == audio_stream_index && audio_callback != nullptr) {
+ audio_callback(&pkt, format_ctx->streams[audio_stream_index]->time_base);
+ }
+ if (pkt.stream_index == video_stream_index) {
+ if (avcodec_send_packet(video_codec_ctx, &pkt) < 0) {
+ fprintf(stderr, "%s: Cannot send packet to video codec.\n", pathname.c_str());
+ *error = true;
+ return AVFrameWithDeleter(nullptr);
+ }
+ } else if (pkt.stream_index == audio_stream_index) {
+ if (*audio_pts == -1) {
+ *audio_pts = pkt.pts;
+ }
+ if (avcodec_send_packet(audio_codec_ctx, &pkt) < 0) {
+ fprintf(stderr, "%s: Cannot send packet to audio codec.\n", pathname.c_str());
+ *error = true;
+ return AVFrameWithDeleter(nullptr);
+ }
+ }
+ } else {
+ eof = true; // Or error, but ignore that for the time being.
+ }
+
+ // Decode audio, if any.
+ if (*audio_pts != -1) {
+ for ( ;; ) {
+ int err = avcodec_receive_frame(audio_codec_ctx, audio_avframe.get());
+ if (err == 0) {
+ convert_audio(audio_avframe.get(), audio_frame, audio_format);
+ } else if (err == AVERROR(EAGAIN)) {
+ break;
+ } else {
+ fprintf(stderr, "%s: Cannot receive frame from audio codec.\n", pathname.c_str());
+ *error = true;
+ return AVFrameWithDeleter(nullptr);
+ }
+ }
+ }
+
+ // Decode video, if we have a frame.
+ int err = avcodec_receive_frame(video_codec_ctx, video_avframe.get());
+ if (err == 0) {
+ frame_finished = true;
+ break;
+ } else if (err != AVERROR(EAGAIN)) {
+ fprintf(stderr, "%s: Cannot receive frame from video codec.\n", pathname.c_str());
+ *error = true;
+ return AVFrameWithDeleter(nullptr);
+ }
+ } while (!eof);
+
+ if (frame_finished)
+ return video_avframe;
+ else
+ return AVFrameWithDeleter(nullptr);
+}
+
+void FFmpegCapture::convert_audio(const AVFrame *audio_avframe, FrameAllocator::Frame *audio_frame, AudioFormat *audio_format)
+{
+ // Decide on a format. If there already is one in this audio frame,
+ // we're pretty much forced to use it. If not, we try to find an exact match.
+ // If that still doesn't work, we default to 32-bit signed chunked
+ // (float would be nice, but there's really no way to signal that yet).
+ AVSampleFormat dst_format;
+ if (audio_format->bits_per_sample == 0) {
+ switch (audio_avframe->format) {
+ case AV_SAMPLE_FMT_S16:
+ case AV_SAMPLE_FMT_S16P:
+ audio_format->bits_per_sample = 16;
+ dst_format = AV_SAMPLE_FMT_S16;
+ break;
+ case AV_SAMPLE_FMT_S32:
+ case AV_SAMPLE_FMT_S32P:
+ default:
+ audio_format->bits_per_sample = 32;
+ dst_format = AV_SAMPLE_FMT_S32;
+ break;
+ }
+ } else if (audio_format->bits_per_sample == 16) {
+ dst_format = AV_SAMPLE_FMT_S16;
+ } else if (audio_format->bits_per_sample == 32) {
+ dst_format = AV_SAMPLE_FMT_S32;
+ } else {
+ assert(false);
+ }
+ audio_format->num_channels = 2;
+
+ int64_t channel_layout = audio_avframe->channel_layout;
+ if (channel_layout == 0) {
+ channel_layout = av_get_default_channel_layout(audio_avframe->channels);
+ }
+
+ if (resampler == nullptr ||
+ audio_avframe->format != last_src_format ||
+ dst_format != last_dst_format ||
+ channel_layout != last_channel_layout ||
+ av_frame_get_sample_rate(audio_avframe) != last_sample_rate) {
+ avresample_free(&resampler);
+ resampler = avresample_alloc_context();
+ if (resampler == nullptr) {
+ fprintf(stderr, "Allocating resampler failed.\n");
+ exit(1);
+ }
+
+ av_opt_set_int(resampler, "in_channel_layout", channel_layout, 0);
+ av_opt_set_int(resampler, "out_channel_layout", AV_CH_LAYOUT_STEREO, 0);
+ av_opt_set_int(resampler, "in_sample_rate", av_frame_get_sample_rate(audio_avframe), 0);
+ av_opt_set_int(resampler, "out_sample_rate", OUTPUT_FREQUENCY, 0);
+ av_opt_set_int(resampler, "in_sample_fmt", audio_avframe->format, 0);
+ av_opt_set_int(resampler, "out_sample_fmt", dst_format, 0);
+
+ if (avresample_open(resampler) < 0) {
+ fprintf(stderr, "Could not open resample context.\n");
+ exit(1);
+ }
+
+ last_src_format = AVSampleFormat(audio_avframe->format);
+ last_dst_format = dst_format;
+ last_channel_layout = channel_layout;
+ last_sample_rate = av_frame_get_sample_rate(audio_avframe);
+ }
+
+ size_t bytes_per_sample = (audio_format->bits_per_sample / 8) * 2;
+ size_t num_samples_room = (audio_frame->size - audio_frame->len) / bytes_per_sample;
+
+ uint8_t *data = audio_frame->data + audio_frame->len;
+ int out_samples = avresample_convert(resampler, &data, 0, num_samples_room,
+ const_cast<uint8_t **>(audio_avframe->data), audio_avframe->linesize[0], audio_avframe->nb_samples);
+ if (out_samples < 0) {
+ fprintf(stderr, "Audio conversion failed.\n");
+ exit(1);
+ }
+
+ audio_frame->len += out_samples * bytes_per_sample;
+}
+
+VideoFormat FFmpegCapture::construct_video_format(const AVFrame *frame, AVRational video_timebase)
+{
+ VideoFormat video_format;
+ video_format.width = width;
+ video_format.height = height;
+ if (pixel_format == bmusb::PixelFormat_8BitBGRA) {
+ video_format.stride = width * 4;
+ } else if (pixel_format == FFmpegCapture::PixelFormat_NV12) {
+ video_format.stride = width;
+ } else {
+ assert(pixel_format == bmusb::PixelFormat_8BitYCbCrPlanar);
+ video_format.stride = width;
+ }
+ video_format.frame_rate_nom = video_timebase.den;
+ video_format.frame_rate_den = av_frame_get_pkt_duration(frame) * video_timebase.num;
+ if (video_format.frame_rate_nom == 0 || video_format.frame_rate_den == 0) {
+ // Invalid frame rate.
+ video_format.frame_rate_nom = 60;
+ video_format.frame_rate_den = 1;
+ }
+ video_format.has_signal = true;
+ video_format.is_connected = true;
+ return video_format;
+}
+
+UniqueFrame FFmpegCapture::make_video_frame(const AVFrame *frame, const string &pathname, bool *error)
+{
+ *error = false;
+
+ UniqueFrame video_frame(video_frame_allocator->alloc_frame());
+ if (video_frame->data == nullptr) {
+ return video_frame;
+ }
+
+ if (sws_ctx == nullptr ||
+ sws_last_width != frame->width ||
+ sws_last_height != frame->height ||
+ sws_last_src_format != frame->format) {
+ sws_dst_format = decide_dst_format(AVPixelFormat(frame->format), pixel_format);
+ sws_ctx.reset(
+ sws_getContext(frame->width, frame->height, AVPixelFormat(frame->format),
+ width, height, sws_dst_format,
+ SWS_BICUBIC, nullptr, nullptr, nullptr));
+ sws_last_width = frame->width;
+ sws_last_height = frame->height;
+ sws_last_src_format = frame->format;
+ }
+ if (sws_ctx == nullptr) {
+ fprintf(stderr, "%s: Could not create scaler context\n", pathname.c_str());
+ *error = true;
+ return video_frame;
+ }
+
+ uint8_t *pic_data[4] = { nullptr, nullptr, nullptr, nullptr };
+ int linesizes[4] = { 0, 0, 0, 0 };
+ if (pixel_format == bmusb::PixelFormat_8BitBGRA) {
+ pic_data[0] = video_frame->data;
+ linesizes[0] = width * 4;
+ video_frame->len = (width * 4) * height;
+ } else if (pixel_format == PixelFormat_NV12) {
+ pic_data[0] = video_frame->data;
+ linesizes[0] = width;
+
+ pic_data[1] = pic_data[0] + width * height;
+ linesizes[1] = width;
+
+ video_frame->len = (width * 2) * height;
+
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(sws_dst_format);
+ current_frame_ycbcr_format = decode_ycbcr_format(desc, frame);
+ } else {
+ assert(pixel_format == bmusb::PixelFormat_8BitYCbCrPlanar);
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(sws_dst_format);
+
+ int chroma_width = AV_CEIL_RSHIFT(int(width), desc->log2_chroma_w);
+ int chroma_height = AV_CEIL_RSHIFT(int(height), desc->log2_chroma_h);
+
+ pic_data[0] = video_frame->data;
+ linesizes[0] = width;
+
+ pic_data[1] = pic_data[0] + width * height;
+ linesizes[1] = chroma_width;
+
+ pic_data[2] = pic_data[1] + chroma_width * chroma_height;
+ linesizes[2] = chroma_width;
+
+ video_frame->len = width * height + 2 * chroma_width * chroma_height;
+
+ current_frame_ycbcr_format = decode_ycbcr_format(desc, frame);
+ }
+ sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes);
+
+ return video_frame;
+}
projects / nageru / blobdiff